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Background: Blood feeding and resting behaviour of malaria vectors are the most influential factors in malaria transmission., Aims: To measure blood feeding and resting behaviour, conventional mosquito sampling methods were performed in an area with potential for malaria transmission., Methods: Adult mosquitoes were collected monthly from indoor/outdoor places by conventional sampling methods, and larval habitats were investigated. Enzyme-linked immunosorbent assay was used to measure the human blood index (HBI) of the mosquitoes., Results: Anopheles stephensi, Anopheles culicifacies, Anopheles dthali and Anopheles fluviatilis, were collected. Overall, 1249 female Anopheles mosquitoes were captured on human and animal baits, but no human-vector contact occurred indoors. A. dthali, A. fluviatilis and A. culicifacies showed a greater tendency to outdoor resting places in contrast to A. stephensi, which had a propensity to indoor resting places. The seasonal biting activities of all species occurred at average temperatures between 23 and 27°C. HBI was measured as 27.2%, 20.7%, 19.1%, and 23.0% for A. fluviatilis, A. stephensi, A. culicifacies and A. dthali, respectively., Conclusion: Vector control strategy depends upon mosquito behaviour. Therefore, using appropriate sampling methods based on mosquito behaviour is critical for malaria control planning. Exophilic/exophagic habit of mosquito vectors leads to fewer human bites, resulting in biting protection. Exophilic behaviour also requires specific larvicidal operations in order to prevent and control malaria transmission., (Copyright © World Health Organization (WHO) 2020. Open Access. Some rights reserved. This work is available under the CC BY-NC-SA 3.0 IGO license (https://creativecommons.org/licenses/by-nc-sa/3.0/igo).)

Objective: To determine the effects of environmental parameters of larval habitats on distribution and abundance of anopheline mosquitoes in Rudan county of Iran., Methods: This cross-sectional study was conducted during the mosquito breeding season from February 2010 to October 2011. The anopheline larvae were collected using the standard dipping method. The specimens were identified using a morphological-based key. Simultaneously with larval collection, environmental parameters of the larval habitats including water current and turbidity, sunlight situation, and substrate type of habitats were recorded. Water samples were taken from breeding sites during larval collection. Before collection of samples, the water temperature was measured. The water samples were analysed for turbidity, conductivity, total alkalinity, total dissolved solid, pH and ions including chloride, sulphate, calcium, and magnesium. Statistical correlation analysis and ANOVA test were used to analyze the association between environmental parameters and larval mosquito abundance., Results: In total 2 973 larvae of the genus Anopheles were collected from 25 larval habitats and identified using morphological characters. They comprised of six species: An. dthali (53.21%), An. stephensi (24.22%), An. culicifacies (14.06%), An. superpictus (4.07%), An. turkhudi (3.30%), and An. apoci (1.14%). The most abundant species was An. dthali which were collected from all of the study areas. Larvae of two malaria vectors, An. dthali and An. stephensi, co-existed and collected in a wide range of habitats with different physico-chemical parameters. The most common larval habitats were man-made sites such as sand mining pools with clean and still water. The anopheline mosquitoes also preferred permanent habitats in sunlight with sandy substrates. The results indicated that there was a significant relationship between mean physico-chemical parameters such as water temperature, conductivity, total alkalinity, sulphate, chloride, and mosquito distribution and abundance., Conclusions: The results of this study showed a correlation between certain environmental parameters and mosquito larvae abundance, and these parameters should be considered in planning and implementing larval control programs., (Copyright © 2013 Hainan Medical College. Published by Elsevier B.V. All rights reserved.)

Long-lasting insecticidal nets (LLINs) have been advocated as an effective tool against malaria transmission. However, success of this community based intervention largely depends on the knowledge and practice regarding malaria and its prevention. According to the national strategy plan on evaluation of LLINs (Olyset nets), this study was conducted to determine the perceptions and practices about malaria and to improve use of LLINs in Bashagard district, one of the important foci of malaria in southeast Iran. The study area comprised 14 villages that were randomized in two clusters and designated as LLINs and untreated nets. Each of households in both clusters received two bed nets by the free distribution and delivery. After one month quantitative data collection method was used to collect information regarding the objectives of the study. On the basis of this information, an educational program was carried out in both areas to increase motivation for use of bed nets. Community knowledge and practice regarding malaria and LLIN use assessed pre- and post-educational program. The data were analyzed using SPSS ver.16 software. At baseline, 77.5% of respondents in intervention and 69.4 % in control area mentioned mosquito bite as the cause of malaria, this awareness increased significantly in intervention (90.3%) and control areas (87.9%), following the educational program. A significant increase also was seen in the proportion of households who used LLINs the previous night (92.5%) compared with untreated nets (87.1%). Educational status was an important predictor of LLINs use. Regular use of LLIN was considerably higher than the targeted coverage (80%) which recommended by World Heaths Organization. About 81.1% and 85.3% of respondents from LLIN and control areas reported that mosquito nuisance and subsequent malaria transmission were the main determinants of bed net use. These findings highlight a need for educational intervention in implementation of long-lasting insecticidal nets; this should be considered in planning and decision-making in the national malaria control program during the next campaigns of LLINs in Iran., (© 2012 Tehran University of Medical Sciences. All rights reserved.)

Background: Malaria continues to be a global public health challenge, particularly in developing countries. Delivery of prompt and effective diagnosis and treatment of malaria cases, detection of malaria epidemics within one week of onset and control them in less than a month, regular disease monitoring and operational classification of malaria are among the major responsibilities of the national malaria programme. The study was conducted to determine these indicators at the different level of primary health care facilities in malaria-affected provinces of Iran, Methods: In this survey, data was collected from 223 health facilities including health centres, malaria posts, health houses and hospitals as well as the profile of all 5, 836 recorded malaria cases in these facilities during the year preceding the survey. Descriptive statistics (i.e. frequencies, percentages) were used to summarize the results and Chi square test was used to analyse data., Results: All but one percent of uncomplicated cases took appropriate and correctly-dosed of anti-malarial drugs in accordance to the national treatment guideline. A larger proportion of patients [85.8%; 95% CI: 84.8 - 86.8] were also given complete treatment including anti-relapse course, in line with national guidelines. About one third [35.0%; 95% CI: 33.6 - 36.4] of uncomplicated malaria cases were treated more than 48 hours after first symptoms onset. Correspondingly, half of severe malaria cases took recommended anti-malarial drugs for severe or complicated disease more than 48 hours of onset of first symptoms. The latter cases had given regular anti-malarial drugs promptly.The majority of malaria epidemics [97%; 95% CI: 90.6 - 100] in study areas were detected within one week of onset, but only half of epidemics were controlled within four weeks of detection. Just half of target districts had at least one health facility/emergency site with adequate supply and equipment stocks. Nevertheless, only one-third of them [33% (95% CI: 0.00 - 67.8)] had updated inventory of malaria foci on quarterly basis., Conclusion: To sum up, malaria case management still constitutes a public health problem in Iran. Additionally, data suggest scarcity in management and evaluation of malaria foci, detection and control of malaria epidemics as well as assignment of emergency sites across different regions of the country. Consequently, massive and substantial investments need to be made at the Ministry of Health to coordinate national malaria control programmes towards achieving determined goals and targets.

Background: Malaria is one of the leading causes of sickness and death in the developing world, causing more than a million deaths and around 250 million new cases annually worldwide. The aim of this comprehensive survey was to provide information on malaria indicators at household level in high-risk malaria areas in Iran., Methods: In a cluster randomized cross-sectional survey data were collected from 5,456 households in both rural and urban areas of 20 malaria-affected districts of Iran. All the fieldwork was done by trained interviewers and a validated questionnaire. The questionnaire comprised baseline characteristics of the study population, the knowledge of people about different aspects of malaria (such as clinical symptoms, transmission and prevention) and their practice to prevent illness (such as using mosquito nets, spraying houses). The data were analysed and descriptive statistics (i.e. frequencies, percentages) were used to summarize the results., Results: The results of this survey showed that 20% (95% CI: 17.36-22.24) of households owned at least one mosquito net, whether treated or untreated. Consequently, the use of mosquito nets was considerably low among both children under age five [5.90% (95% CI: 5.14-6.66)] and pregnant women [5.70% (95% CI: 3.07-8.33)]. Moreover, less than 10% of households reported that the interior walls of their dwelling had been sprayed in the previous year [8.70% (95% CI: 6.09-11.31)]. Data also suggest that 63.8% of the participants recognized fever as a sign of malaria, 56.4% reported that mosquito bites cause malaria and about 35% of participants mentioned that the use of mosquito nets could prevent malaria., Conclusion: Findings from this study indicate that low access to treated nets along with low understanding of the role of nets in malaria prevention are the main barriers to utilization of bed nets. Therefore, the use of insecticide-treated mosquito nets should be encouraged through health education on the importance of the use along with increasing access to it.

Background: Malaria remains endemic at low levels in the south-eastern provinces of Iran bordering Afghanistan and Pakistan, with the majority of cases attributable to P. vivax. The national guidelines recommend chloroquine (CQ) as blood-stage treatment for uncomplicated P. vivax, but the large influx of imported cases enhances the risk of introducing CQ resistance (CQR). Methodology and Principal Findings: The genetic diversity at pvmdr1, a putative modulator of CQR, and across nine putatively neutral short tandem repeat (STR) markers were assessed in P. vivax clinical isolates collected between April 2007 and January 2013 in Hormozgan Province, south-eastern Iran. One hundred blood samples were collected from patients with microscopy-confirmed P. vivax enrolled at one of five district clinics. In total 73 (73%) were autochthonous cases, 23 (23%) imported cases from Afghanistan or Pakistan, and 4 (4%) with unknown origin. 97% (97/100) isolates carried the F1076L mutation, but none carried the Y976F mutation. STR genotyping was successful in 71 (71%) isolates, including 57(57%) autochthonous and 11 (11%) imported cases. Analysis of population structure revealed 2 major sub-populations, K1 and K2, with further sub-structure within K2. The K1 sub-population had markedly lower diversity than K2 (HE = 0.06 vs HE = 0.82) suggesting that the sub-populations were sustained by distinct reservoirs with differing transmission dynamics, possibly reflecting local versus imported/introduced populations. No notable separation was observed between the local and imported cases although the sample size was limited. Conclusions: The contrasting low versus high diversity in the two sub-populations (K1 and K2) infers that a combination of local transmission and cross-border malaria from higher transmission regions shape the genetic make-up of the P. vivax population in south-eastern Iran. There was no molecular evidence of CQR amongst the local or imported cases, but ongoing clinical surveillance is warranted. [ABSTRACT FROM AUTHOR]

Objective To determine some bio-ecological aspects of malaria vectors in Jask County, where is targeted for malaria elimination in the national program. Methods Mosquitoes were collected monthly during 2013–2014 using different collection methods. Subsequently, ELISA test was used to detect the human blood index of mosquitoes. The susceptibility status of Anopheles stephensi was evaluated against the diagnostic dosages of seven WHO recommended insecticides. Results A total of 3 650 female and 4 736 Anopheles larvae were collected including Anopheles stephensi , Anopheles culicifacies s.l., Anopheles dthali , Anopheles fluviatilis s.l., Anopheles moghulensis and Anopheles turkhodi species. Anopheles stephensi was the dominant collected species on human baits and indoors with high rate of unfed and gravid specimens in internal and external window traps. Human blood index was calculated as 14.3% for this species. It was also found to be resistant to DDT and Dieldrin. Conclusions The collected species had a wide range of habitats, and resting behaviors. With regarding to the presence of most important malaria vectors in Jask, control of the disease may be so complicated; as based on the weather condition it can be transmitted during the whole year, expect for cold months. With this strong potential of transmission, existing population movements in the area may lead to imported cases of malaria and local outbreak(s). So, more specific studies on malaria vectors in high risk areas of Jask County are recommended. [ABSTRACT FROM AUTHOR]

Background: Malaria is an endemic infectious disease in southeastern parts of Iran. Despite years of efforts and intervention programs against malaria, transmission still occurs in Jask County. Methods: The epidemiological perspective of malaria in Jask County was conducted by gathering data from Jask County health center, during 2006-2010. A knowledge, attitude and practice study was also carried out. Data analysis was conducted using SPSS ver. 11.5. Results: A total of 2875 malaria cases were recorded, with highest and lowest numbers in 2007 and 2010, respectively. The number of cases had a decreasing trend from 1022 cases in 2006 to 114 cases in 2010. The main causative parasitic agent was Plasmodium vivax. Blood examination rate and slide positive rate were also decreased from 39.5% and 4.3% in 2006 to 15.6% and 1.4% in 2010, respectively. Most of people interviewed in the KAP study had a good knowledge about malaria transmission and symptoms but their use of the bed net for prevention was low (35%). Conclusion: Malaria incidence had significant reduction during the study years. The main reason for this may be due to changing environmental condition for Anopheline breeding and survival because of drought. Another reason may be integration of vector management by using long lasting insecticide treated bed nets, active case detection and treatment by implementation of mobile teams and increasing in financial sources of malaria control program. Knowledge, attitude and practice of people were good in malaria control and prevention, but needs to do more activities for health education and awareness. [ABSTRACT FROM AUTHOR]

Long-lasting insecticidal nets (LLINs) have been advocated as an effective tool against malaria transmission. However, success of this community based intervention largely depends on the knowledge and practice regarding malaria and its prevention. According to the national strategy plan on evaluation of LLINs (Olyset nets), this study was conducted to determine the perceptions and practices about malaria and to improve use of LLINs in Bashagard district, one of the important foci of malaria in southeast Iran. The study area comprised 14 villages that were randomized in two clusters and designated as LLINs and untreated nets. Each of households in both clusters received two bed nets by the free distribution and delivery. After one month quantitative data collection method was used to collect information regarding the objectives of the study. On the basis of this information, an educational program was carried out in both areas to increase motivation for use of bed nets. Community knowledge and practice regarding malaria and LLIN use assessed pre- and post-educational program. The data were analyzed using SPSS ver.16 software. At baseline, 77.5% of respondents in intervention and 69.4 % in control area mentioned mosquito bite as the cause of malaria, this awareness increased significantly in intervention (90.3%) and control areas (87.9%), following the educational program. A significant increase also was seen in the proportion of households who used LLINs the previous night (92.5%) compared with untreated nets (87.1%). Educational status was an important predictor of LLINs use. Regular use of LLIN was considerably higher than the targeted coverage (80%) which recommended by World Heaths Organization. About 81.1% and 85.3% of respondents from LLIN and control areas reported that mosquito nuisance and subsequent malaria transmission were the main determinants of bed net use. These findings highlight a need for educational intervention in implementation of long-lasting insecticidal nets; this should be considered in planning and decision-making in the national malaria control program during the next campaigns of LLINs in Iran. [ABSTRACT FROM AUTHOR]

Background: In malaria endemic areas, continuous exposure to Plasmodium parasites leads to asymptomatic carriers that provide a fundamental reservoir of parasites, contributing to the persistence of malaria transmission. Therefore, in the present investigation, the presence and prevalence of malaria asymptomatic cases were determined to evaluate the reservoir of infection in two malaria endemic areas with a previous history of malaria transmission in the south of Iran, Bashagard and Ghale-Ganj districts of Hormozgan and Kerman provinces, respectively, where malaria transmission has been drastically reduced in the recent years. Methods: The population samples (n = 500 from each of the studied areas) were randomly collected from non-febrile, long-term residing, aged two to over 60 years, during 2009-2010. Three identical surveys were carried out in both study areas and in each phase all the consent participants were interviewed and clinically examined. In all, three surveys to detect hidden parasite reservoirs (both Plasmodium falciparum and Plasmodium vivax), thick and thin blood smears and a highly sensitive nested-PCR were applied. In addition, the sero-prevalence survey for detecting malaria exposure was done by using a serological marker. Results: In this study, P. vivax and P. falciparum parasites were not detected by light microscopy and nested-PCR assay in all three surveys of samples. Antibody responses against P. vivax and P. falciparum were detected in 1 % and 0.2 % of the total examined individuals, respectively, in Bashagard district. Regarding to Ghale-Ganj district, about 0.9% of the individuals had IgG -specific antibody to P. vivax at the first and second surveys, but at the third survey 0.45% of the participants had positive antibody to P. vivax parasite. IgG -specific antibody to P. falciparum was detected in 0.2% of the participants at the first and follow-up surveys. The overall regional differences were not statistically significant (P>0.05). Conclusion: Taken together, the lack of asymptomatic carrier with the evidence of extremely low sero-positive to both P. vivax and P. falciparum among examined individuals supported the limited recent transmission in the studied areas and, therefore, these parts of Iran have potential to eliminate the disease in the next few years. However, continued follow up and action are still needed in both studied areas and also in their neighbouring province, Sistan and Baluchistan, which has the highest reported cases of malaria in Iran and also, has the largest border line with Afghanistan and Pakistan, with no elimination activities. This data will provide useful information for managing elimination activities in Iran. [ABSTRACT FROM AUTHOR]